Pneumatically power operated nailing machine



Oct. 12, 1965 E. P. ANSTETT 3,211,352

PNEUMATICALLY POWER OPERATED NAILING MACHINE Filed July 25, 1962 4 Sheets-Sheet l I- INVENTOR.

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Oct. 12, 1965 E. P. ANSTETT 3,211,352

PNEUMATICALLY POWER OPERATED NAILING MACHINE Filed July 23, 1962 I 4 Sheets-Sheet 2 F J arji iz BY WW PNEUMATICALLY POWER OPERATED NAILING MACHINE Filed July 25, 1962 E.P.ANSTETT Oct. 12, 1965 4 Sheets-Sheet 3 IN VENTOR. @47 2 Mai PNEUMATICALLY POWER OPERATED NAILING MACHINE Filed July 25, 1962 E. P. ANSTETT Oct. 12, 1965 4 Sheets-Sheet 4 United States Patent 3,211,352 PNEUMATICALLY POWER OPERATED NAILING MACHINE Edgar P. Anstett, 21 Lakewood Place, Highland Park, Ill.

, Filed July 23, 1962, Ser. No. 211,551

12 Claims. (Cl. 227136) The principal object of this invention is to provide a pneumatically power operated nailing machine for severing and driving nails from an elongated nailing strip, which is particularly adaptable for severing and driving headed nails from nailing strips of the kind disclosed in my copending applications Serial No. 211,733 and Serial No. 211,809, now Patent No. 3,165,968, filed on even date herewith, which is lightweight and compact in construction so as to be readily and conveniently manipulated and used, which utilizes minimum parts and which is simple but yet rugged in construction so as to provide long life with minimum repairs or adjustments, which utilizes a double acting pneumatic motor means for its power actuation so as to eliminate the need for return springs or the like and to require only minimum volume of air under pressure, which utilizes a simple valve means for the pneumatic motor means for providing fool-proof and maximum nail driving force by the motor means, which utilizes a simple but accurate die means cooperating with a blade driven by the pneumatic motor means for accurately sequentially severing and driving nails from the nailing strip, which utilizes a simple but effective means for guiding and advancing the nailing strip to the die means and for providing for ready insertion of nailing strips into the machine, which is provided with a convenient trigger means for manually controlling the operation of the machine, and which is provided with a manually manipulatable safety means for preventing inadvertent operation of the machine.

Briefly, the pneumatically power operated nailing machine of this invention includes a housing having a bottom portion, a head portion at one end of the bottom portion and a handle portion above the bottom portion and connecting with the head portion and the other end of the bottom portion. The head portion adjacent the bottom portion carries a die means which movably receives the nailing strip and sequentially centers the nails therein as the nailing strip is advanced. The bottom portion carries means for guiding and advancing the nailing strip to the die means. A movable blade is arranged in the head portion in alignment with the die means and it is advanced and retracted in cooperation with the die means for sequentially severing and driving nails from the advancing nailing strip.

A pneumatic motor means is arranged in the head portion and it is connected to the blade for advancing and retracting the same. The head and handle portions contain a reservoir of air under pressure and valve means in the bottom portion controls the supply of air under pressure from the reservoir to the pneumatic motor means to operate the same for advancing and retracting the blade. A trigger member is arranged adjacent the handle portion for manually operating the valve means to retract the blade when the trigger member is released and to advance the blade, when the trigger member is actuated, for severing and driving a nail from the nailing strip. The bottom portion is also provided with a manually manipulatable safety means for preventing inadvertent movement of the valve means.

The pneumatic motor means in the head portion is a double acting pneumatic motor means including a pair of concentric cylinders of different diameters and a differential area piston movable in the cylinders and connected to the blade for moving the blade.

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The smaller area of the piston communicates directly with the reservoir of air under pressure for advancing the blade in the nail severing and driving direction with substantially no change in air pressure. The valve means in the bottom portion in its normal position supplies air under pressure from the reservoir to the larger area of the piston for normally retracting the blade. When the valve means is operated from its normal position, it rapidly dumps air from the larger area of the piston to allow the air under pressure on the smaller area of the piston to rapidly advance the blade for severing and driving the nail from the nailing strip in a Single blow.

An O-ring is arranged in the smaller diameter cylinder for sealing the smaller area of the piston therein. A resilient bumper seal is carried by the larger area of the piston for sealing the same in the larger diameter cylinder, and a resilient bumper seal is carried by the larger diameter cylinder for sealing the blade therein. The resilient bumper seals engage each other, when the piston and blade are substantially completely advanced, to resiliently decelerate the advancing movement of the piston and blade. A vent passage to atmosphere is located in the larger diameter cylinder adjacent the smaller diameter cylinder, and the larger area portion of the piston restricts the vent passage, when the piston is substantially completely retracted, to pneumatically decelerate the retracting movement of the piston and blade.

The valve means in the bottom portion is a three Way valve including a valve body having a longitudinal passage provided with a first port at one end communicating with the larger area of the piston, a second port at the other end communicating with the reservoir of air under pressure, and a third port inter-mediate its ends communicating with the atmosphere. A hollow tubular valve member is slidably received in the longitudinal passage. When the valve member is in its normal position, the first port is closed and the second port is open for supplying air under pressure through the hollow tubular member to the larger area of the piston for normally retracting the blade. When the valve member is moved to its operating position by the trigger member, the second port is closed and the first port is opened for rapidly dumping air from the larger area of the piston through the first and third ports to atmosphere to allow the air under pressure on the smaller area of the piston to rapidly advance the blade for severing and driving a nail from the nailing strip in a single blow.

The means for guiding and advancing the nailing strip includes an elongated guide member carried by the bottom portion of the housing and extending from the die means. The guide member includes guide means for guiding the nailing strip from the remote end of the guide member to the die means and, also, guide tracks parallel to the guide means. A feeder member is slidably carried by the guide tracks and engages the trailing end of the nailing strip. A roller is carried by the feeder member, and a normally rolled ribbon spring is secured at one end to the roller and at its other end to the guide member adjacent the die means for resiliently advancing the feeder member and hence the nailing strip toward the die means. The feeder member is provided witha resilient finger normally engageable with the free end of the guide member for holding the feeder member in retracted position to facilitate insertion of the nailing strip in the guide means and depressible to allow advancing movement of the feeder member along the guide tracks by the ribbon spring.

The die means which cooperates with the advancing and retracting blade for severing and driving nails from the nailing strip includes a die member and a stripper bushing superimposed over the die member, the die member and the stripper bushing being provided with holes therethrough conforming to the blade and the heads of the nails severed and driven from the nailing strip. The die member is also provided with a slot therein communieating with the hole therein to allow the nails of the advancing nailing strip to reach the hole. The die abutting face of the stripper bushing is provided with a groove for receiving and guiding the advancing nailing strip between the die member and the stripper bushing. A projection is arranged in the groove adjacent the hole in the stripper bushing for indexing the advancing nailing strip as headed nails are severed and driven therefrom by the blade advancing and retracting through the holes in the stripper bushing and die member.

Further objects of this invention reside in the details of construction of the pneumatically power operated nailing machine and in the cooperative relationships between the component parts thereof.

Other objects and advantages of this invention will become apparent to those skilled in the art upon reference to the accompanying specification, claims and drawings in which:

FIG. 1 is an end elevational view of the pneumatically power operated nailing machine looking from the rear;

FIG. 2 is an enlarged vertical sectional view through the nailing machine taken substantially along the line 2-2 of FIG. 1;

FIG. 3 is an enlarged sectional view through the guiding and advancing means for the nailing strip, taken substantially along the lines 3-3 of FIGS. 1 and 4;

FIG. 4 is a horizontal sectional view through the guiding and advancing means taken substantially along the line 44 of FIG. 3;

FIG. 5 is a horizontal sectional view through the valve means taken substantially along the line 5-5 of FIG. 2;

FIG. 6 is a vertical sectional view through the guiding and advancing means taken substantially along the line 66 of FIG. 2;

FIG. 7 is a vertical sectional view taken substantially along the line 77 of FIG. 2;

FIG. 8 is a vertical sectional view taken substantially along the line 88 of FIG. 2;

FIG. 9 is a horizontal sectional view taken substantially along the line 9-9 of FIG. 2;

FIG. 10 is a vertical sectional view taken substantially along the lines 10-10 of FIGS. 2 and 9;

FIG. 11 is a perspective view of the stripper bushing of the die means;

FIG. 12 is a perspective view,of the die member of the die means;

FIG. 13 is an enlarged vertical sectional view similar to the lower left hand portion of FIG. 2 illustrating the nailing strip about to be severed and driven therefrom;

FIG. 14 is a horizontal sectional view taken substantially along the line 14-14 of FIG. 13;

FIG. 15 is an enlarged sectional view of a portion of the apparatus illustrated in FIG. 13 but illustrating a headed nail being severed and driven from the nailing strip;

FIG. 16 is a'vertical sectional view of a severed headed nail; and

FIG. 17 is a perspective view of the severed headed nail.

The pneumatically power operated nailing machine of this invention is generally designated at 10 in FIGS. 1 and 2 and it is utilized for severing and driving nails from a nailing strip 11 which is shown in more detail in FIGS. 13 to 17. Here, the nailing strip 11 may be of the kind disclosed in my aforementioned copending application Ser. No. 211,733 and, in this respect, it may include a molded synthetic plastic strip 12 which is provided with longitudinally spaced'recesses 13 and longitudinally spaced nipples 14 concentrically arranged with the recesses 13. Headed nails are carried by the strip 11, the shanks 15 of the nails being gripped and secured by the nipples 14 of the strip and the heads 15 being received in the recesses 13 in the strip. A plurality of slots 17 are arranged between the headed nails and these slots 17 are for the purpose of indexing the nailing strip as the headed nails are severed and driven therefrom.

The pneumatically power operated nailing machine 10, as shown in FIGS. 1 and 2, comprising a housing 20 which includes a bottom portion 21, a head portion 22 at one end of the bottom portion, and a handle portion 23 above the bottom portion extending from the head portion to the other end of the bottom portion. The interior of the handle portion 23 and the upper part of the head portion 22 constitutes a reservoir 24 for air under pressure. The lower end of the head portion 22 is provided with a foot 26 which is secured in place by screws 27. The foot 26 is provided with a downwardly extending hollow semicylindrical portion 28 with the open side thereof extending rearwardly. It is also provided with a pair of bosses 29 extending laterally from the portion 28 which receive adjusting screws 30 which extend downwardly along side of the portion 28. These adjusting screws 30, if desired, are adapted to contact the work being nailed for positioning the nailing machine with respect to the work. These adjusting screws 30 may be adjusted by suitably rotating the same and they are held in adjusted position by spring pressed balls 31. The top of the foot 26 is provided with a central cylindrical hole 32 and with a rearwardly extending entrance groove 33 and a forwardly extending exit groove 34 communicating with the central hole 32. The entrance groove 33 receives and guides the nailing strip 11 to the central hole 32 and the exit groove 34 receives and guides the waste material of the nailing strip 12 from the central hole 32.

The central hole 32 of the foot 26 receives a die means consisting of a die member 36 and a stripper bushing 37, shown in more detail in FIGS. 11 and 12. The die member 36 and the stripper bushing 37 are suitably pinned together by pins extending through holes 38 therein. The die member 36 is provided with a central hole 39 which conforms to the configuration of the headed nail to be severed and driven from the nailing strip 11 and it is also provided with a slot 40 communicating with the hole 39 to allow the feeding of the nail shanks 15 to the central hole 39. The stripper bushing 37 also includes a central hole 41 conforming to the central hole 39 of the die member 36. The face of the stripper bushing 37 which abuts against the face of the die member 36 is pro vided with a groove 42 thereacross for receiving and guiding the nailing strip. On the exit side of the stripper bushing 37 the groove is provided with a central projectron 43 which is sequentially engaged by the slots 17 in the nailing strip 11 for indexing the nailing strip, namely for centering the headed nails of the nailing strip in the open ngs 39 and 41 in the die member 36 and the stripper bushing 37 so that headed nails may be accurately severed and driven from the nailing strip. The die means, includlng the die member 36 and the stripper bushing 37, are received in the central hole 32 in the foot 26 and they are held in place therein by a plate 46 overlying the foot 26. An O-ring seal 45 in the stripper bushing 37 operates to seal a severing and driving blade 60 which is advanced and retracted through the central holes in the stripper bushing 37 and the die member 36.

The nailing strip 11 is guided and advanced to the die means 36, 37 by an advancing and guiding means including a guide member 47 which is suitably attached to the bottom portion 21 of the housing. As shown more clearly in FIGS. 6 and 8, the guide member 47 is provided with guide means for the nailing strip including a guide groove 48 receiving the strip 12 and a guide surface 49 engaged by the nail shanks 15. The guide member is also provided with a pair of guide tracks 50 and 51 which receive and guide a feeder member 52. The feeder member 52 is provided with an abutment 53 which engages a notch in the trailing end of the nail strip 11 for advancing the same. The feeder member 52 rotatably carries a roller 54 by means of a pin 55. One end of a normally rolled ribbon spring 56 is secured to the roller 54 and the other end thereof is secured to the forward end of the guide member 47 as indicated at 57. Since the ribbon spring 56 winds upon itself, it operates to advance the feeder member 52 along the guide tracks 50 and 51 for advancing the nailing strip. The ribbon spring 56, when the feeder member 52 is retracted, rests flat against the inner face of the guide member 47. The feeder member 52 is also provided wiith a resilient finger 58 which is adapted to engage the rear end of the guide member 47, as shown more clearly in FIG. 3, for holding the feeder member 52 in its retracted position against the action of the ribbon spring 56. By so doing, the insertion of the nailing strip into the guide member 47 is greatly facilitated, the nailing strip being inserted into the foot 26 and laterally into the guide groove 48 when the feeder member is retracted. After the nailing strip 11 is inserted in the guide member 47, the resilient finger 58 is depressed to allow it to enter the guide track 58 whereupon the ribbon spring 56 advances the feeder member 52 and hence the nailing strip 11.

As the nailing strip is advanced and the blade 60 retracted, a slot 17 in the strip 12 engages the projection 43 in the groove 42 of the stripper bushing 37 so as to center the nail shank 15 with respect to the blade 60. When the blade 60 is advanced, it severs a headed nail from the nailing strip and in so doing it cuts through the strip 12 and the slots 17 around the nail head 16 so as to sever a headed nail from the strip as shown in FIG. 15. As the headed nail is so severed, the nipple portion 14 and a circular portion of the strip 12 around the head 16 of the headed nail is driven with the headed nail into the work being nailed.

The blade 60, which cooperates with the die member 36 and the stripper bushing 37 to sever and drive nails from the nailing strip 11, is cylindrical in configuration and conforms to the holes 39 and 41 in the die member 36 and stripper bushing 37 and it is provided at its upper end with a flange 61 which engages and is secured to a piston of a pneumatic motor means. The pneumatic motor means includes a piston portion 64 of relatively large area and a piston portion 65 of relatively small area, the piston, therefore, being a differential piston. The larger area portion 64 of the piston is slidably received in a cylinder 66 of larger diameter in the head portion 22 of the housing 20 and the smaller area portion 65 is received in a smaller diameter cylinder 67 also in the head portion 22 of the housing 20. The smaller area portion 65 of the piston is sealed by an O-ring 68 carried in the smaller diameter cylinder 67. The smaller area portion 65 of the piston is exposed to the air under pressure in the reservoir 24, this air under pressure normally operating to advance the piston in a downwardly nail severing and driving direction. A resilient bumper seal 69 is suitably secured to the larger area portion 64 of the piston and it is provided with an annular lip 70 for sealing the larger area portion 64 of the piston in the larger diameter cylinder 66. The resilient bumper seal 69 is also provided with an annular lip 71 for sealing the blade 60. The bottom of the larger diameter cylinder 66 is also provided with a resilient bumper seal 72 which in turn is provided with an annular lip 73 for sealing the cylinder 66 and with an annular lip 74 for also sealing the blade 60. The resilient bumper seals 69 and 72 are similar in construction and may be formed from any suitable resilient sealing material such as rubber, neoprene or the like.

When air under pressure is supplied to the larger diameter portion or area 64 of the piston, the piston is retracted since the area of the portion 64 is greater than the area of the portion 65. This movement retracts the blade 60. When, however, the air under pressure in the cylinder 66 is vented to atmosphere, the air under pressure acting on the smaller area portion 65 of the piston advances the piston and hence the blade 60. When the piston is substantially completely advanced, the resilient bumper seal 69 engages the resilient bumper seal 72 to decelerate the motion of the piston and hence the blade 60. A vent passage 75 is provided in the larger diameter cylinder 66 adjacent the smaller diameter cylinder 67 so as to allow atmospheric pressure to exist between these two cylinders. When the differential piston is retracted by the application of air under pressure below larger diameter portion 64 of the differential piston, the air trapped above it discharges through the vent 75. When the differential piston reaches substantially its upper position, the larger diameter portion 64 of the piston throttles the vent passage 75 so as to pneumatically decelerate the retracting movement of the piston.

Air under pressure is supplied through a suitable fitting 78 received in a tapped hole 77 in the handle portion 73 of the housing 20 so as to maintain a substantially constant air pressure in the reservoir 24. The head portion 22 of the housing 20 may be provided with a tapped hole 79 for receiving a pressure gauge or a plug 80, as illustrated in FIG. 2.

The supply of air under pressure below the larger diameter portion 64 of the differential piston and the exhaust of air therefrom is controlled by a valve means located in the bottom portion 21 of the housing 20. The valve means includes a longitudinal bore or passage 82 in the bottom portion 21. The bore 82 is closed at its rearward end by a plug 83. The forward end of the passage 82 is provided with a first port 84 communicating with the larger diameter cylinder 66. The bore or passage 82 is provided adjacent its rearward end with a port 85 communicating with the reservoir 24. Intermediate its ends the passage 82 is provided with an annular port 86 which communicates laterally with the atmosphere through an opening 99 and side openings 108. A cylindrical tubular valve member 87 is slidably mounted in the bore or passage 82 and it is provided with an internal passage 88 extending from one end to the other of the valve member. The forward end of the bore or passage 82 is provided with a seal 89 for sealing the valve member 87 when it is in its forward position. The passage or bore 82 is also provided with a seal 90 for sealing the valve member 87 against the escape of air from the reservoir 24 when it is in its rearward position. A snap washer assembly 91 is received in a groove in the valve member 87 and is arranged within the third port 86. A spring 92 is interposed between this washer assembly 91 and a washer 93 engaging a shoulder in the bore or passage 82. The spring 92 operates to normally resiliently urge the valve member 87 forwardly to the position illustrated in FIGS. 2 and 5. A trigger member 95 is pivoted at 96 to the housing 20 and it is provided with a finger portion 97 for manually manipulating the same and a bifurcated portion 98 extending through the opening 99 into the third port 86 in engagement with the washer assembly 91.

When the valve member 87 is in its forward normal position as determined by the spring 92, the valve member 87 seals the port 84 and opens the port 85 whereby air under pressure flows from the reservoir 25 through the internal passage 88 in the valve member 87 into the cylinder 66 for applying air under pressure against the larger area portion 64 of the differential piston. As a result, the differential piston and the blade 60 are retracted. When, however, the finger portion 97 of the trigger 95 is manipulated, the bifurcated end 98 of the trigger member retracts the valve member 87 against the action of the spring 92. This retracting movement closes the port 85 to interrupt the flow of air from the reservoir 24 to the larger diameter cylinder 86 and it also opens the port 84 into communication with the discharge port 86. As a result, the air under pressure in the larger diameter cylinder 66 is rapidly dumped to atmosphere through ports 84 and 86 and the openings 99 and 100. This allows the air under pressure acting on the smaller diameter portion 65 of the differential piston to rapidly advance the differential piston and the blade 60. When the finger portion 97 of the trigger member 95 is released, the spring 92 again retracts the valve member 87 to the position illustrated in FIGS. 2 and 5 so as to retract the differential piston and the blade 60.

The bottom portion 21 of the housing is also provided with a transverse slot 101 for accommodating a manually manipulatable safety means. In this connection the valve member 87 is provided with a reduced diameter portion 102 which is arranged within a safety member 103 slidably mounted in the transverse slot 101. The safety member 103 is provided with a keyhole slot 104, as illustrated more clearly in FIGS. 5 and 8. When the member 103 is in the position illustrated, the smaller portion of the keyhole slot 104 prevents longitudinal movement of the valve member 87 and locks it in its normal position to prevent manipulation of the valve member 87. When, however, the member 103 is manually manipulated to its other position where the larger portion of the keyhole slot is in alignment with the valve member 87, the valve member 87 may be advanced by the trigger member 95 against the action of the spring 92.

Summarizing briefly the operation of the nailing machine of this invention, the nailing strip 11 is guided and advanced by the guiding means and the advancing movement is indexed by the projection 43 engaging the slots 17 in the strip 11, as shown more clearly in FIGS. 13 and -14. When the trigger member 95 is manipulated to advance the differential piston and the blade 60, the blade 60 severs and drives a headed nail from the nailing strip 11 as shown in more detail in FIG. 15. A single stroke of the pneumatically power operated nailing machine operates to sever the headed nail and drive the same from the nailing strip 11 into the work in a single blow. When the trigger member 95 is released, the pneumatic motor and the blade 60 are retracted and the guiding and advancing means then operates to advance the nailing strip until such time as the next slot 17 therein engages the projection 43. Thereafter, the operation of the machine is repeated by manipulation of the trigger member 95.

While for purposes of illustration one form of this invention has been disclosed, other forms may become apparent to those skilled in the art upon reference to this disclosure and, therefore, this invention should be limited only by the scope of the appended claims.

I claim as my invention:

1. In a pneumatically power operated nailing machine for severing and driving nails from an elongated nailing strip and including die means movably receiving the nailing strip and sequentially centering the nails therein as the nailing strip is advanced, means guiding and advancing the nailing strip to the die means, and a movable blade aligned and cooperating with the die means and advanced and retracted for sequentially severing and driving nails from the advancing nailing strip, the improvement comprising, double acting pneumatic motor means including a dilferential area piston connected to the blade for moving the blade, a reservoir continuously supplying air under pressure to the smaller area of the piston for advancing the blade in the nail severing and driving direction, means including a single three way valve movable to a normal position for supplying air under pressure to the larger area of the piston for normally retracting the blade and movable to an operating position for rapidly dumping air from the larger area of the piston to allow the air under pressure on the smaller area of the piston to rapidly advance the blade for severing and driving a nail from the nailing strip in a single blow, spring means normally moving said single three way valve to its normal position, and manually operated means for moving said single three way valve from its normal position to its operating position against the action of said spring means.

2. In a pneumatically power operated nailing machine for severing and driving nails from an elongated nailing strip and including die means movably receiving the nailing strip and sequentially centering the nails therein as the nailing strip is advanced, means guiding and advancing the nailing strip to the die means, and a movable blade aligned and cooperating with the die means and advanced and retracted for sequentially severing and driving nails from the advancing nailing strip, the improvement comprising, double acting pneumatic motor means including a differential area piston connected to the blade for moving the blade, a reservoir of air under pressure communicating directly and freely with the smaller area of the piston for advancing the blade in the nail severing and driving directions with substantially no change in air pressure, means including a single three way valve movable to a normal position for supplying air from the reservoir to the larger area of the piston for normally retracting the blade and movable to an operating position for rapidly dumping air from the larger area of the piston to allow the air under pressure on the smaller area of the piston to rapidly advance the blade for severing and driving a nail from the nailing strip in a single blow, spring means normally moving said single three way valve to its normal position, and manually operated means for moving said single three way valve from its normal position to its operating position against the action of said spring means.

3. In a pneumatically power operated nailing machine for severing and driving nails from an elongated nailing strip and including die means movably receiving the nailing strip and sequentially centering the nails therein as the nailing strip is advanced, means guiding and advancing the nailing strip to the die means, and a movable blade aligned and cooperating with the die means and advanced and retracted for sequentially severing and driving nails from the advancing nailing strip, the improvement comprising, double acting pneumatic motor means including a differential area piston connected to the blade for moving the blade, a reservoir continuously supplying air under pressure to the smaller area of the piston for advancing the blade in the nail severing and driving direction, a three way valve including a valve body having a longitudinal passage provided with a first port at one end communicating with the larger area of the piston, a second port at the other end communicating with a source of air under pressure and a third port intermediate its ends communicating with the atmosphere, and a hollow tubular valve member slidably received in the longitudinal passage, spring means normally moving the hollow tubular valve member to a normal position closing the first port and opening the second port for supplying air under pressure through the hollow tubular valve member to the larger area of the piston for normally retracting the blade, and manually operated means for moving the hollow tubular valve member against the action of the spring means to an operating position closing the second port and opening the first port for rapidly dumping air from the larger area of the piston through the first and third ports to atmosphere to allow the air under pressure on the smaller area of the piston to rapidly advance the blade for severing and driving a nail from the nailing strip in a single blow.

4. In a pneumatically power operated nailing machine for severing and driving nails from an elongated nailing strip and including die means movably receiving the nailing strip and sequentially centering the nails therein as the nailing strip is advanced, means guiding and advancing the nailing strip to the die means, and a movable blade aligned and cooperating with the die means and advanced and retracted for sequentially severing and driving nails from the advancing nailing strip, the improvement comprising, double acting pneumatic motor means including a differential area piston connected to the blade for moving the blade, a reservoir of air under pressure communicating directly and freely with the smaller area of the piston for advancing the blade in the nail severing and driving direction with substantially no change in air pressure, a three way valve including a valve body having a longitudinal passage provided with a first port at one end communicating with the larger area of the piston, a second port at the other end communicating with the reservoir and a third port intermediate its ends communicating with the atmosphere, and a hollow tubular valve member slidably received in the longitudinal passage, spring means normally moving the hollow tubular valve member to a normal position closing the first port and opening the second port for supplying air under pressure through the hollow tubular valve member from the reservoir to the larger area of the piston for normally retracting the blade, and manually operated means for moving the hollow tubular valve means against the action of the spring means to an operating position closing the second port and opening the first port for rapidly dumping air from the larger area of the piston through the first and third ports to atmosphere to allow the air under pressure on the smaller area of the piston to rapidly advance the blade for severing and driving a nail from the nailing strip in a single blow.

5. In a pneumatically power operated nailing machine for severing and driving nails from an elongated nailing strip and including die means movably receiving the nailing strip and sequentially centering the nails therein as the nailing strip is advanced, means guiding and advancing the nailing strip to the die means, and a movable blade aligned and cooperating with the die means and advanced and retracted for sequentially severing and driving nails from the advancing nailing strip, the improvement comprising, double acting pneumatic motor means including a diiferential area piston connected to the blade for moving the blade, a reservoir continuously supplying air under pressure to the smaller area of the piston for advancing the blade in the nail severing and driving direction, means including a single three way valve movable to a normal position for supplying air under pressure to the larger area of the piston for normally retracting the blade and movable to an operating position for rapidly dumping air from the larger area of the piston to allow the air under pressure on the smaller area of the piston to rapidly advance the blade for severing and driving a nail from the nailing strip in a single blow, spring means normally urging said single three Way valve to its normal position, manually operated means for moving said single three way valve from its normal position to its operating position against the action of said spring means, and manually manipulatable safety means for preventing inadvertent move-ment of said single three way valve from its normal position to its operating position.

6. In a pneumatically power operated nailing machine for severing and driving nails from an elongated nailing strip and including die means movably receiving the nailing strip and sequentially centering the nails therein as the nailing strip is advanced, means guiding and advancing the nailing strip to the die means, and a movable blade aligned and cooperating with the die means and advanced and retracted for sequentially severing and driving nails from the advancing nailing strip, the improve-ment comprising, double acting pneumatic motor means including a differential area piston connected to the blade for moving the blade, a reservoir continuously supplying air under pressure to the smaller area of the piston for advancing the blade in the nail severing and driving direction, a single three way valve including a valve body having a longitudinal passage provided with a first port at one end communicating with the larger area of the piston, a second port at the other end communicating with a source of air under pressure and a third port intermediate its ends communicating with the atmosphere, and a hollow tubular valve member slidably received in the longitudinal passage, spring means normally moving the hollow tubular valve member to a normal position closing the first port and opening the second port for supplying air under pressure through the hollow tubular valve member to the larger area of the piston for normally retracting the blade, manually operated means for moving the hollow tubular valve member against the action of the spring means to an operating position closing the second port and opening the first port for rapidly dumping air from the larger area of the piston through the first and third ports to atmosphere to allow the air under pressure on the smaller area of the piston to rapidly advance the blade for severing and driving a nail from the nailing strip in a single blow, and safety means including an annular groove in the hollow tubular valve member and a manually manipulatable slide member in the valve body having a key-hole slot cooperating with the annular groove for preventing inadvertent movement of the valve member from its normal position to its operating position.

7. In a pneumatically power operated nailing machine for severing and driving nails from an elongated nailing strip and including die means movably receiving the nailing strip and sequentially centering the nails therein as the nailing strip is advanced, means guiding and advancing the nailing strip to the die means, and a movable blade aligned and cooperating with the die means and advanced and retracted for sequentially severing the driving nails from the advancing nailing strip, the improvement comprising, double acting pneumatic motor means including a pair of concentric cylinders of different diameters and a differential area piston movable in said cylinders and connected to the blade for moving the blade, a reservoir continuously supplying air under pressure to the smaller area of the piston for advancing the blade in the nail severing and driving direction, means including a single three way valve for supplying air under pressure to the larger area of the piston for normally retracting the blade, and for rapidly dumping air from the larger area of the piston to allow the air under pressure on the smaller area of the piston to rapidly advance the blade for sequentially severing the driving nails from the nailing strip in single blows, a resilient bumper seal carried by the larger area of the piston and sealing the same in the larger diameter cylinder, and a resilient bumper seal carried by the larger diameter and sealing the blade therein, said resilient bumper seals engaging when the piston and blade are substantially completely advanced to resiliently decelerate the advancing movement of the piston and blade.

8. In a pneumatically power operated nailing machinemor severing and driving nails from an elongated nailing strip and including die means movably receiving the nailing strip and sequentially centering the nails therein as the nailing strip is advanced, means guiding and advancing the nailing strip to the die means, and a movable blade aligned and cooperating with the die means and advanced and retracted for sequentially severing and driving nails from the advancing nailing strip, the improvement comprising, double acting pneumatic motor means including a pair of concentric cylinders of dilferent diameters and a differential area piston movable in said cylinders and connected to the blade for moving the blade, a reservoir continuously supplying air under pressure to the smaller area of the piston for advancing the blade in the nail severing and driving direction, means including a single three way valve for supplying air under pressure to the larger area of the piston for normally retracting the blade, and for rapidly dumping air from the larger area of the piston to allow the air under pressure on the smaller area of the piston to rapidly advance the blade for sequentially severing and driving nails from the nailing strip in single blows, means for sealing the larger and smaller areas of the piston in the larger and smaller diameter cylinders respectively, and a vent passage to atmosphere in the larger diameter cylinder adjacent the smaller diameter cylinder, said larger area portion of the piston restricting said vent passage when the piston is substantially completely retracted to pneumatically decelerate the retracting movement of the piston and blade.

9. In a pneumatically power operated nailing machine for severing and driving nails from an elongated nailing strip and including die means movably receiving the nailing strip and sequentially centering the nails therein as the nailing strip is advanced, means guiding and advancing the nailing strip to the die means, and a movable blade aligned and cooperating with the die means and advanced and retracted for sequentially severing and driving nails from the advancing nailing strip, the improvement comprising, double acting pneumatic motor means including a pair of concentric cylinders of different diameters and a differential area piston movable in said cylinders and connected to the blade for moving the blade, a reservoir continuously supplying air under pressure to the smaller area of the piston for advancing the blade in the nail severing and driving direction, means including a single three way valve for supplying air under pressure to the larger area of the piston for normally retracting the blade, and for rapidly dumping air from the larger area of the piston to allow the air under pressure on the smaller area of the piston to rapidly advance the blade for sequentially severing and driving nails from the nailing strip in single blows, an O-ring in the smaller diameter cylinder for sealing the piston of smaller area therein, a resilient bumper seal carried by the larger area of the piston and sealing the same in the larger diameter cylinder, a resilient bumper seal carried by the larger diameter cylinder and sealing the blade therein, said resilient bumper seals engaging when the piston and blade are substantially completely advanced to resiliently decelerate the advancing movement of the piston and blade, and a vent passage to atmosphere in the larger diameter cylinder adjacent the smaller diameter cylinder, said larger area portion of the piston restricting said vent passage when the piston is substantially completely retracted to pneumatically decelerate the retracting movement of the piston and blade.

10. A nailing machine for severing and driving nails from an elongated nailing strip comprising a housing including a bottom portion, a head portion at one end of the bottom portion and a handle portion above the bottom portion and connecting with the head portion and the other end of the bottom portion, die means in the head portion adjacent the bottom portion movably receiving the nailing strip and sequentially centering the nails therein as the nailing strip is advanced, means on the bottom portion for guiding and advancing the nailing strip to the die means, a movable blade in the head portion aligned and cooperating with the die means and advanced and retracted for sequentially severing and driving nails from the advancing nailing strip, pneumatic motor means in the head portion connected to the blade for moving the blade, a reservoir of air under pressure in the head and handle portions, valve means in the bottom portion only for controlling the supply of air under pressure from the reservoir through said other end of the bottom portion to the pneumatic motor means to operate the same to advance and retract the blade, and a trigger member adjacent the handle portion mechanically connected to the valve means in the bottom portion for manually operating the same to retract the blade when the trigger member is released and to advance the blade when the trigger member is actuated to advance the blade for severing and driving a nail from the nailing strip.

11. In a power operated nailing machine for severing and driving nails from an elongated nailing strip having a strip portion and nails carried thereby and including die means movably receiving the nailing strip and sequentially centering the nails therein as the nailing strip is advanced, and a power operated blade aligned and cooperating with the die means and advanced and retracted for sequentially severing and driving nails from the advancing nailing strip, the improvement comprising, an elongated guide member extending from the die means and including a guide groove for laterally receiving and guiding the strip portion of the nailing strip from the remote end of the guide member to the die means and opposed grooves parallel to the guide groove, a feeder member slidably carried by the opposed grooves and engaging the trailing end of the strip portion of the nailing strip, a roller carried by the feeder member, and a normally rolled ribbon spring secured at one end to the roller and at its other end to guide member adjacent the die means for resiliently advancing the feeder member and hence the nailing strip toward the die means.

12. In a power operated nailing machine for severing and driving nails from an elongated mailing strip having a strip portion and nails carried thereby and including die means movably receiving the nailing strip and sequentially centering the nails therein as the nailing strip is advanced, and a power operated blade aligned and cooperating with the die means and advanced and retracted for sequentially severing and driving nails from the advancing nailing strip, the improvement comprising, an elongated guide member extending from the die means and including a guide groove for laterally receiving and guiding the strip portion of the nailing strip from the remote end of the guide member to the die means and opposed grooves parallel to the guide groove, a feeder member slidably carried by the opposed grooves and engaging the trailing end of the strip portion of the nailing strip, a roller carried by the feeder member, a normally rolled ribbon spring secured at one end to the roller and at its other end to guide member adjacent the die means for resiliently advancing the feeder member and hence the nailing strip toward the die means, and a resilient finger on the feeder member normally engageable with the free end of the guide member for holding the feeder member in retracted position to facilitate lateral insertion of the strip portion of the nailing strip in the guide groove and depressible to allow advancing of the feeder member along the opposed grooves by the ribbon spring.

References Cited by the Examiner UNITED STATES PATENTS 2,784,405 3/57 Working 1-56 X 2,923,937 2/60 Laucher 144.4 2,947,003 8/60 Ericsson 144.4 2,989,750 6/61 McIlvin l-44.4 X 3,055,344 9/62 Fisher 144.4 X 3,056,965 10/62 Rogers 1106 3,086,207 4/63 Lingle et al 144.4

GRANVILLE Y. CUSTER, JR., Primary Examiner. 

1. IN A PNEUMATICALY POWER OPERATED NAILING MACHINE FOR SEVERING AND DRIVING NAILS FROM AN ELONGATED NAILNG STRIP AND INCLUDING DIE MEANS MOVABLE RECIEVIN THE NAILING STRIP AND SEQUENTIALLY CENTERING THE NAILS THEREIN AS THE NAILING STRIP IS ADVANCED, MEANS GUIDING AND ADVANCING THE NAILING STRIP TO THE DIE MEANS, AND A MOVABLE BLADE ALIGNED AND COOPERATING WITH THE DIE MEANS AND ADVANCED AND RETRACED FOR SEQUENTIALLY SEVERING AND DRIVING NAILS FROM THE ADVANCING NAILING STRIP, THE IMPROVEMENT COMPRISING, DOUBLE ACTING PNEUMATIC MOTOR MEANS INCLUDING A DIFFERENTIAL AREA PISTON CONNECTED TO THE BLADE FOR MOVING THE BLADE, A RESERVOIR CONTINUOUSLY SUPPLYING AIR UNDER PRESSURE TO THE SMALLER AREA OF THE PISTON FOR ADVANCING THE BLADE IN THE NAIL SEVERING AND DRIVING DIRECTION, MEANS INCLUDING A SINGLE THREE WAY VALVE MOVABLE TO A NORMAL POSITION FOR SUPPLYING AIR UNDER PRESSURE TO THE LARGER AREA OF THE PISTON FOR NORMALLY RETRACTING THE BLADE AND MOVABLE TO AN OPERATING POSITION FOR RAPIDLY DUMPING AIR FROM THE LARGER AREA OF THE PISTON TO ALLOW THE AIR UNDER PRESSURE ON THE SMALLER AREA OF THE PISTON TO RAPIDLY ADVANCE THE BLADE FOR SEVERING AND DRIVING A NAIL FROM THE NAILING STRIP IN A SINGLE BLOW, SPRING MEANS NORMALLY MOVING SAID SINGLE THREE WAY VALVE TO ITS NORMAL POSITION, AND MANUALLY OPERATED MEANS FOR MOVING SAID SINGLE THREE WAY VALVE FROM ITS NORMAL POSITION TO ITS OPERATING POSITION AGAINST THE ACTION OF SAID SPRING MEANS, 